Investigation of the effect of using NSM method in repairing cracked concrete beams under static torsional loading

Document Type : Original Article

Author

Faculty of Civil Engineering, Iran university of science and technology, Tehran, Iran.

Abstract

Most concrete cracks are due to incorrect designs and incorrect execution methods. One of the designs that should be done for concrete parts is the design for twisting. The amount of torsion is significant in edge beams or beams that are connected to the slab on one side, so if a crack occurs on the concrete parts due to torsion, it should be repaired using different methods. One of the existing methods is to use GFRP rebars inside concrete under the title of using NSM method to repair concrete. In this research, by making concrete parts with dimensions of 15 × 15 × 120 cm and creating cracks on them, they are repaired using The NSM method and the effect of using that method on the components of the final torsional anchor, the final torsional force and the final torsional angle have been investigated. The results showed that the use of this method increased the torsional strength of cracked concrete beams by 9.52 times.

Keywords


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